1211231321 has 8 divisors (see below), whose sum is σ = 1220278080. Its totient is φ = 1202204592.

The previous prime is 1211231309. The next prime is 1211231339. The reversal of 1211231321 is 1231321121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1211231321 - 2³⁰ = 137489497 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1211231321.

It is not an unprimeable number, because it can be changed into a prime (1211231341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 129635 + ... + 138663.

It is an arithmetic number, because the mean of its divisors is an integer number (152534760).

Almost surely, 2^1211231321 is an apocalyptic number.

It is an amenable number.

1211231321 is a deficient number, since it is larger than the sum of its proper divisors (9046759).

1211231321 is an equidigital number, since it uses as much as digits as its factorization.

1211231321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10015.

The product of its digits is 72, while the sum is 17.

The square root of 1211231321 is about 34802.7487563842. The cubic root of 1211231321 is about 1065.9635738439.

Adding to 1211231321 its reverse (1231321121), we get a palindrome (2442552442).

It can be divided in two parts, 121 and 1231321, that multiplied together give a palindrome (148989841).

The spelling of 1211231321 in words is "one billion, two hundred eleven million, two hundred thirty-one thousand, three hundred twenty-one".